1. Field of Invention
The present invention relates generally to the harvest of agricultural materials such as alfalfa and, specifically, to an assembly for continuously forming bales of the agricultural material without a need to stop while a bale is being finished before beginning a new bale.
2. Description of Other Art
Farm operators have long used various machines and processes to gather agricultural materials. Where the materials include plant materials such as leaves and stems, the general process includes cutting the plants and, usually, raking them into windrows where they are left to dry for a period of time. The operator may then go through the field with a rake to turn the windrow and expose more material drying.
Once adequately dried, the operator employs a machine that comprises a pick up mechanism (and perhaps a windrower elevator) to gather the dried material into a baler. There are many different balers; come create small rectangular bales easily hefted by a person, some produce larger rectangular bales more likely to be moved by machines, some produce large round bales that may only be moved with adequate power machinery. Each of these balers further includes a chamber into which the agricultural material is conveyed. In this chamber are means to shape and compress the material into the general bale shape and means to secure the baled materials together Securing the material may include tying cord, wire or twine, or wrapping a mesh-like wrap over it, or some combination thereof.
In order for the baler to tie or wrap the bale it must stop to allow time for that operation and avoid gathering more materials. If it did not stop gathering material, that material would be problematic for the tying operation. To avoid the negative impact of stopping for the formation of every bale a number of new apparatuses have been developed. Some employ a mechanism to move the formed bale into a different part of the chamber for tying. (see, e.g., U.S. Pat. Nos. 6,729,118; 5,136,831; 4,667,592; 4,656,812; 4,534,285; 4,510,861). In many cases this is accomplished via tension-loaded belts and rollers wherein the position of the rollers move in order to transition the forming bale from an early stage compartment near the leading edge of the baler (near the windrow pickup) to a later stage compartment near the trailing edge of the baler. The compartments are, at least in part, formed by the positions of the tensioned belts. Essentially, the baling unit is divided into the two chambers and these change in size via movement of the belts and rollers through the bale forming process. The first area expands with the growing bale until it reaches a certain size (and certain level of tension on the belts). Then, through movement of the rollers and the associated belts, the trailing edge of the early stage compartment is opened and the forming bale is moved toward the back of the round baler into what becomes the later stage compartment where the bale is wrapped and/or tied. While it is being wrapped and/or tied, the early stage chamber is still receiving forage and beginning to form the core of the next bale.
Some balers in this general format have the bale completely formed in the first chamber, and merely wrap/tie in the latter. Others form the core in one chamber, and then finish the bale in the second chamber where it is also wrapped and tied. The chambers can be arranged laterally as described herein, or vertically. Sometimes the transition from one chamber to the other is assisted by a mechanical arm (U.S. Pat. No. 4,625,502). Still another invention employs a conveyor from the windrow pick up and a moveable physical obstruction between the first and second chambers to effect means to continuously bale. (U.S. Pat. Nos. 4,057,954; 4,514,969).
Most of the aforementioned attempts to remove the need to stop during bale formation are complex machines with multiple moving parts and are fairly expensive. Further, they are usually replacements for the balers already owned by operators rather than providing a solution to be employed with the original balers in which the farm operators have invested.
What was needed was a resolution to the problem of time loss and wear on equipment caused by regularly stopping forward movement across the field, without the prohibitive cost of a dual baler system.